Energy, such as ultrasound energy, can be applied to treat tissue or perform traditionally invasive procedures in a non-invasive manner. The application of ultrasound energy provides both thermal and/or mechanical effects that help treat certain ailments such as acne and enable many traditional invasive procedures to be performed non-invasively.
Current ultrasound devices provide energy to tissue within a region of interest. The energy is emitted from an ultrasound system and travels a certain depth within the tissue and has an effect on the tissue. The effect can be ablative, coagulative, non-ablative, or non-coagulative and is generally caused by the thermal and/or mechanical properties that ultrasound has on tissue. Thermal properties increase the temperature of the tissue at the region of interest while the mechanical effects are achieved by cavitation, streaming, radiation force, and other natural mechanical effects of ultrasound.
Further, ultrasound energy has certain spatial and temporal properties when it is applied to the region of interest. The “temporal” properties refer to the time that the ultrasound energy is applied while the “spatial” properties refer to the space within the tissue that is affected by the ultrasound energy at a specific moment in time.
While effective, existing ultrasound devices only affect a specific portion of the tissue at a certain depth within the region of interest based upon the configuration of the ultrasound device. For example, an ultrasound device might be configured to affect an area five millimeters below the surface of the skin. The tissue from the surface of the skin to the depth of five millimeters is spared and not treated by the ultrasound energy. Sparing these intervening spaces of tissue hinders the overall beneficial effect of ultrasound as treatment of this intervening tissue increases ultrasound treatment's overall efficacy.
Therefore, it would be beneficial to provide an ultrasound device and treatment method that treats multiple areas of tissue in a region of interest including intervening tissue and even the distal layer of tissue. It would also be advantageous to provide a system and method that treated numerous depths of tissue by varying the spatial and temporal effects of ultrasound at different depths such has having ablative or coagulative ultrasound applied to certain depths of tissue while non-ablative ultrasound is applied to other depths of tissue.